Kadin makes a snowman by stacking snowballs of radius 2 inches, 3 inches, and 5 inches.  Assuming all his snowballs are spherical, what is the total volume of snow he uses, in cubic inches?  Express your answer in terms of $\pi$.
A sphere with radius $r$ has volume $\frac{4}{3}\pi r^3$.  Thus, the snowballs with radius 2, 3, and 5 inches have volumes $\frac{4}{3}\pi(2^3)$, $\frac{4}{3}\pi(3^3)$, and $\frac{4}{3}\pi(5^3)$ cubic inches respectively.  The total volume of snow used is thus  \begin{align*}
\frac{4}{3}\pi(2^3)+\frac{4}{3}\pi(3^3)+\frac{4}{3}\pi(5^3)&=\frac{4}{3}\pi(2^3+3^3+5^3)\\
&=\frac{4}{3}\pi(8+27+125)\\
&=\boxed{\frac{640}{3}\pi}.\end{align*}